A typical busway contains multiple busbar conductors sandwiched together and installed within a metal housing to form the busway. Each busbar conductor can carry a different phase of electrical current (sometimes referred to as a pole) or a neutral current and therefore must be dielectrically insulated from adjacent busbar conductors to prevent cross-phase electrical shorts and from the grounded metal busway housing to prevent ground faults. The busway can be of a feeder type, for long straight runs of electrical current, or a plug-in type, which allows for the connection of plug-in or bolt-on devices to branch circuits. Busways carry massive amounts of electrical current and get hot as a result. Thus, thermal management of a busway is an important consideration because heat reduces the overall current-carrying efficiency of the busway as some of the energy carried by the busbars is dissipated and lost as heat before it reaches an intended electrical load. Another important consideration is the mechanical integrity of the busway, especially during a short circuit event, where electromagnetic or electro-dynamic forces produced during a short circuit event operate to repel the conductors away from one another, compromising the electrical and mechanical integrity of the busbars and the busway housing. Busway designers have struggled to balance increasing the busway's mechanical strength while improving its thermal performance, all the while making the busway smaller, lighter, stronger, and more efficient.
Moreover, some busbars are coated on all exposed surfaces with a dielectric epoxy powder, which is allowed to cure, but during the curing process, tiny pinholes can appear at random places through the cured epoxy coating that expose the metal busbar. These holes can be responsible for creating undesired current paths from the busbar conductor when energized to the grounded busbar housing, so they need to be plugged. But first, any holes that exist need to be located, which is a labor-intensive process that involves, in one known dielectric test, sweeping an energized brush across the entire surface of both sides of the epoxy coating of an energized busbar while monitoring for a leakage current to identify a hole in the coating. Once a hole is discovered, the epoxy around the discovered hole can be drilled to make it larger, and then an epoxy is manually applied to the drilled hole and allowed to cure. This discovery and curing process can take up to an hour or more per busbar per busway. The integrity of all dielectric interfaces between energized conductors and energized and grounded surfaces must be maintained to ensure that no unintended current paths exist in the busway.
What is needed is an improved system and method of assembling a busway that yields an optimum level of mechanical strength and thermal performance and has unassailable dielectric integrity between and among grounded and energized conducting surfaces. Aspects of the present disclosure address these and other needs.